1. Field of the Invention
The present invention generally relates to a fluid filter. More specifically, the present invention is drawn to a plastic injection molded frame for holding air filter media in a furnace.
2. Description of the Related Art
Almost all central air heating systems used in modern homes require an air filter. The purpose of the air filter is to rid the incoming air of dust and pollen which may cause breathing difficulties. Filtering the incoming air is especially critical for those who suffer from allergic reactions which are triggered by pollen/dust borne air.
Many heating systems position the air filter in a guide track located in the air inlet duct. Typically, the air filter is a unit comprising filter media encased in a cardboard frame and covered with wire mesh. When the filter media becomes laden with pollen and dust, the entire unit (cardboard frame, wire mesh, and filter media) is removed from the guide track for disposal and replaced with a new unit. The above filter replacement process is expensive in that the relatively costly cardboard frame and wire mesh are wastefully disposed.
The following patents show other types of air filter arrangements. U.S. Pat. No. 3,076,303 (Durgeloh) discloses air filter media encased around its perimeter by a plastic frame. U.S. Pat. No. 5,464,461 (Whitson et al.) discloses an air filter unit for an avionic line replacement unit box. U.S. Pat. No. 5,725,623 (Bowerman et al.) discloses an air filter unit for a vacuum cleaner. Japanese Patent 62-74426 discloses media encased around its perimeter by a metallic frame.
None of the above inventions and patents, taken either singularly or in combination, is seen to disclose a plastic injection molded furnace filter unit as will be described and claimed in the present invention.